Switching device



Jan. 20, 1959 G. H. RUFLE SWITCHING DEVICE Filed Feb. 25, 1955 INVENTOR. GEORG H. RUFLE HTTORNE'Y ai-a United States Patent '0 SWITCHING DEVICE George l L'Rutle, New'York, N. Y.

Application February 25,1955, Serial No..490,503

9 Claims. (Cl.' 200'87) 'tandcimproveddevice for opening .andclosing an electri- ,.'c al.circuit, inwhich thereis a movable circuit closing imembersupported upon afiuid, the fluid being electrically conductive and maintainingelectrical contact with the .imovable circuit closingfimember inall dispositions of "said member.

A furtherobjcctof the invention is to providea novel andimproved switch closing device in which there are "twoelectrical: terminals connectable into a circuit to be opened and'closed, one of the electrical terminals being p'rovided with -a relatively stationary electrode, and the other terminal being provided with a relatively movable electrode, thesecond electrode being supported buoy- 1 -antly in'or on atluidwhich is electrically conductive, and

-=gives the movable electrode-springy upward bias ina cir- -cuit closing direction, the fluid being in conductive conrtact-with the second terminal, whereby as an insulating card, tape, or other circuit opening device is disposed intermediate the stationary and movable electrodes, it blocks circuit closing engagement therebetween, where- -as, when said insulating card is either withdrawn, or has an opening in said card presented into registry with said electrodes, allowing said movable electrode to extend therethrou'gh, the circuit is again brought into normally closed position.

-Sti ll anotherobject of the invention is to provide a novel and improved circuit opening and closing device inwhichnovel means are provided whereby the'buoyancy *giving fluid is arranged in-suchfashion as to avoid substantially any spilling of the fluid from the housing in which-.is it disposed, due to any causes, such as tipping to a very substantial angle of'inclination, or due to the .rapidity of rnotionof the movable electrode.

Still a further object o'f-the invention is to provide a noveland improved circuit opening and closing device, in which there are a pair of electrical terminals connectable'in'a circuit-to be opened and closed, the first of the terminals being provided with a metallic electrode ,or plate disposed in the path of movement of the second electrode, the second electrode being disposed floatably upon a metallic liquid such as liquid mercury, which is electrically conductive, andmaintains contact'with both the second electrode and the second electrical tterminal, the mercury liquid being disposed in a hollow cylinder orotherco-ntainer in which the fioatable electrode is movable and is automatically centered in such movement.

Another object of the invention is to provide a novel and improved normally closed switch in which one of "ice the movablewelectrodesis floated on a pool of mercury :liquid. and. is given bias by said mercury into circuit closing movement, the movable electrode being in the form .of a spherical member floating on said mercury, with outwardly extending disc or other shaped centering-means blocking rotation of thespherical member, and thus avoiding outward spilling movement of the mercuryfrom its container.

A further object ofthe invention is to provide a novel circuitopening. and closing. device, in which one ormore circuits are sequentially or in any desired sequence opened and closed, under the controlof cards with intermittent perforations or intermittent conductive-sectionsor tapes or other similar circuit controlling means.

Still another object of .the invention is to providea ;novel and improved circuit opening and closing device,

and/or.machineincorporatinga plurality of said devices for predetermined sequential circuit opening-and closing of multiple circuits, which is simple in design, inexpensive to manufacture, rugged and long lived in use, and highlypetlectivein operation for its intended purposes.

These. and other objects and advantages of the invention will become apparent from the following description of a preferred embodiment thereof, as illustrated in the accompanying drawings, forming a part hereof, and in which,

Figure 1.is a sectional elevational view of one form of circuit closing element.

Figure ,2 is a sectional plan view taken substantially on plane 2-2 of'Figure l, and showing the variousparts thereof.

Figure 3 is a fragmentary sectional elevational view of the invention.

Figure 4 is a sectional elevational view, showing a further modified form of the invention, in fragment.

FigureS is a sectional plan view taken on a plane like that of Figure 2, but showing a modified form of device, with rectangular configuration.

Figure 6 is a sectional elevational view showing another .modified form of the invention, with spherical movable electrode, in highest dispositon of the electrode.

Figure 7 is a sectional elevational view similar to that of Figure 6, except showing the spherical electrode in depressed circuitopen position.

Figure 8 is a top plan view of the device shown in Figure 6.

Figure 9 is a sectional elevational view showing a device of the kind .shownin Figure l, witha second electrode plate disposed out of contact with the movable electrode.

Figure 10 is a sectional elevational view similar to that of Figure 9, but showing the upper contact plate moved into engagement with the movable electrode.

Figure 11 is a sectional elevational view similar to that ofEFigure 10, but showing a circuit interrupting card or tape extending between the electrodes to cpcnthe circult, and depressing the movable electrode.

Figure 12 is a sectional elevational view showing a plurality of circuit closing electrodes with a punched card extending therebetween and the fixed electrode, and employing permanent magnets above the fixed electrode.

Figure 13 is a sectional elevational view showing another modified form of circuit arrangement with card carrying intermittently conductive areas or lines passing therethrough, and showing use of electromagnetic pull enhancing means.

Figure 14 is a view similar to that of Figure 1'3, but showing the disposition of the movable electrode when the electromagnetis tie-activated, opening the circuit.

In connection with the manufacture and use of circuit opening and closing devices, resort has been commonly asvoass 3 had to use of either pivoted switch blades, of spring biased blades. For rapidly opening and closing circuits, the spring biased blades are subject to many disadvantages which are well known in the art, including continuous diminution of the biasing effect due to aging or mechanical working of the spring elements, even where phosphor bronze of even beryllium copper are employed. The present device avoids such disadvantages by supporting the closing contact with the relatively stationary electrode,

with considerable decrease in cost of maintenance and operation.

In order to understand clearly the nature of the invention, and the best means for carrying it out, reference may now be had to the drawings, in which like numerals denote similar parts throughout the several views.

As shown, there is a main switch housing generally indicated at 20, which may be of any suitable contour, such as with cylindrical side walls 22, extending upwardly from the floor 24, to their upper edges 26, so as to define a cylindrical or otherwise shaped upwardly open chamber 28, for the reception of liquid mercury 30, or other suitable liquid having similar characteristics. A movable electrode member is generally shown at 32, and is pro vided with an enlarged upper portion or head 34, which is greater in outside diameter than the cylindrical housing 20, and thus blocks further downward movement of the movable electrode member 32 once its head 34 rests upon the upper edge 26 of the side walls 22 of the housing 20.

As shown, there is an intermediate or body portion 38 of the movable electrode member 32, which is small enough in outside diameter to easily slide within the bore of chamber 28, without undue binding, and without blocking freepassage of air into and out of chamber 28 around the outside of body portion 38, the body portion 38 being preferably integral with head 34. A central post member 48, made of electrically conductive material, such as steel or other metal not subject to chemical interaction by contact with mercury, is seated at its upper end in a socket 42 formed in the intermediate body 38, and is thus movable therewith. Since in this form of the invention, the intermediate body 38 and the head 34 are both made of steel, such as magnetizable steel, and the central post member 48 is similarly made of metal such as steel or other suitable metal, it is apparent that when the contact post member 46 is immersed in the mercury liquid 28, there is at all times electrical contact between the head 34 of the movable electrode 32, and the stationary contact screw 44 which is actually the one terminal of the switch shown, and is connectable by wire 46 into any circuit to be opened and closed thereby.

In order to aid in buoyancy of the steel body 38 and head 34, in one form of the invention, I prefer to dispose a small sleeve or collar float member 48 with the rod 40 extending through an axial hole 50 in the float member 48, so that the float member moves with the rod 40 and the rest of the movable electrode 32. The float member 48 may be of any suitable material, such as cork, plastic composition, or other suitable float material which has suflicient buoyancy to aid in allowing the lower end 52 of the float to rest upon the upper surface of the mercury liquid 30. Since the outside diameter of the float member 48 is less than the inside diameter of the mercury chamber 28, it is seen that when the plunger electrode 32 is depressed, as seen best in Figures and 11, there is room around the outside of the float 48 for the displaced mercury liquid to go, as at 56 in Figure 11. It is also apparent that by using the lower float collar 48, it is possible to attain suflicient buoyancy while the upper surface of the mercury 30 remains well below the top 26 of the housing 20, and thus there is little chance of spillage of mercury even if the housing 28 is tipped to a substantial degree, and also during high speed up and down oscillations of the plunger contact electrode 32.

From Figure 1, it is also seen that mercury will assume a convex upper surface contour, as at 60, when disposed in the chamber 28 without the plunger 32 in position. When the electrode plunger 32 is placed in the position in the housing 20 as seen in Figures 1 and 9, the float member 48 will have a tendency to flatten or depress the central portion of the meniscus or convexity of the mercury upper surface, which will thus have a tendency to try to elevate the float member and to thus recover its initial convexity. This thus is a sort of spring eflect, giving the float member 48 and the parts carried thereby, an upward springy bias, depending upon their weight.

As seen in Figure 1, the rounded upper end or head 34 of the plunger electrode 32, is hence biased upwardly continuously into contact with the stationary electrode plate 62, which may be of steel or other metal, and connectable by wire 64, into a circuit with bottom lead wire 46 as the other terminal. In Figure l, the circuit is closed between wires 46 and 64, by the contact between the plate 62 and the upper end or head 34 of the plunger electrode 32. This corresponds to Figure 10 also. However it is seen that the plate 62 itself may be made movable, that is, initially, or at any given time, as seen in Figure 9, so that when the plate 62 is in its retracted upper position shown in Figure 9, it is out of contact engagement with the plunger 32 even when that contact is in its uppermost position as shown. Now then, when by any suitable positioning means, the contact plate 62 is moved to circuit closing position shown in Figure 10, it is seen that the switch formed thereby is closed normally. Referring now to Figure 11, it is seen that an insulating card of paperboard, plastic, or tape, seen at 66, may now be passed through from right to left, under plate 62, and so as to cam downwardly the head 34 of the plunger 32, thus opening the circuit between wires 46 and 64, and depressing the plunger 32 sufliciently as to force some mercury up into the space as at 56 surrounding the float collar 48 of the plunger electrode 32.

The card 66 may be provided with one or more openings 70, formed therethrough, as at the upper right of Figure 11, and also shown in Figure 12, large enough for the rounded head 34 or the tip thereof to extend through into contact with the plate 66, and thus close the switching circuit when the opening reaches registry with the head 34, opening again when the opening has passed thereby. Referring now to Figure 12, it is seen that here there is the similar arrangement, but that permanent magnets 72 may be disposed above the plate 62, to exert enhanced upward pull on the steel plunger electrodes 32, 32a, 3211, etc, to augment the upward bias furnished by the buoyancy of the floating on the mercury liquid in chamber 28. This arrangement is important particularly to enhance the upward bias on the plunger electrodes 32, but also to prevent leakage or spillage of any of the mercury as for some unknown reason, or failure to keep it filled to the proper level, so that if there is any mercury at all in the chamber 23, such as shown in the rightward chamber 28 in Figure 12, the buoyancy of the mercury will not be relied upon to hold up the plunger electrode 320, since the electric magnet or permanent magnet 72 will exert the necessary upward bias thereon, the card 66 serving like in Figure 11, to break the circuit at all points except where the holes 70 are located. Where magnetic upward pull is relied upon as at 72 in Figure 12, or also in Figures 13 and 14, it is apparent that the stationary contact plate 62 will have to be made of some other conductive material than tsteel or iron,

'5 such as brassycopper, or other materials, so that such material will not shield the magnetic flux from the mag nets from coming down through the plate 62 to exert shown open in Figure 14 and closed in Figure 13. Here it is seen that when theelectromagnet 80 is energized by .closing. switch 88, as in Figure 1 3, there is an added upward p'ull exerted by the magnet 80, which not only enhances the upward bias of the convex mercury surface in housing 20, but even maintains upward bias on the plunger electrode 32 when there is just a little mercury in the chamber 28, thus keeping the device in operation should mercury be not filled to the proper level, or for some reason or other, have been spilled out. In Figures 13 and 14, another form of circuit making and interrupting card or tape is shown at 66b, which may, for example, have local conductive areas as at 90, imprinted or marked in carbon, ink, or metallic imprint at predetermined intervals, making contact with the head 34 of the electrode 32, with a common ground interconnecting all such markings along a margin of the tape or card, for example and connected to plate 62, or the tape 66b may be conductive, with insulating areas as at 90, to interrupt the circuit, any desired arrangement being possible as needed in particular situations.

Referring now to Figure 4, it is seen that here is a modified form of the invention, which is somewhat similar to that of Figure 1, except that instead of reducing the float 48 in diameter to allow ingress of displaced mercury, the lower end portion of the main body 38 may be reduced somewhat as shown at 96, with a cylindrical contour above the lower bulge 98, and an annular inner space or groove 100 formed around the portion 90 to receive displaced mercury as needed.

Figure 5 shows how instead of a cylindrical contour for the members shown in Figures 1 and 2, a rectangular contour may be used for the housing 200, the head 34c of the plunger 32, with the reduced lower body 38c and the rod 400, the head being rounded at each end like that at 34 in Figure 1, but flattened somewhat at the sides.

Figures 8, 7 and 6 shows another modified form of the invention, in which there is a housing 20d which is cylindrical and has mercury 30 disposed in its chamber 28d to float the spherical steel or iron float ball 110. A collar 112 is carried on the ball for motion therewith, the collar being slidable vertically in the enlarged bore portion of chamber 28d, as the contact ball 110 coming in contact with the plate 62 closes the circuit, and when a card or tape is inserted therebetween depressing the ball, opens the circuit as in Figure 7, the collar blocking rotation of ball 110.

According to another modified form of the invention, the device shown in Figures 1 and 2 may be modified by making the head 34, the body 38, and the lower body 48, all integrally of plastic composition which will lighten it so much as to make it all floatable on the mercury at the mercury surface 52 or thereabouts. The rod 40e is carried right all the way upwardly through the entire body and head 34c, being enlarged at the top to form a contact element. Figure 3 shows this in some detail.

Although I have described my invention in specific terms, it will be understood that various changes may be made in size, shape, materials and arrangement without departing from the spirit and scope of the invention as claimed.

I claim:

l. A switching device comprising first and second terminal means, a housing defining a chamber, conductive liquid disposed in said chamber and connected electrically to said second terminal means, movable circuit closing means supported by said conductive liquid so as to be upwardly biased by said liquid into contact engagement normally with said first terminal means to close said cir- -cuit-of, -sa idswitching device, said movable circuit closing ,means being inherently electrically conductive, whereby, upon movernent of a circuit opening element between said circuit closing means and said first terminal means,

said switchingv device circuitis opened and whereinsaid conductive liquid ismercury, said movable circuit closing means comprising-a body of insulating material floatable on said mercury liquid so-as to be biased upwardly thereby, rodmeans extending through said body from top to bottom, and extending downwardly therebeyond, to maintain electrical contact -.with saidliquid mercury, while the upper end of said rod means isconstructed and arranged for forming electrical contact with said first ,terminal means when free from insulating means therebetween, and displaced fluid controlling receiving means for receiving mercury displaced upon depression of said floatable body.

2. A switching device comprising first and second terminal means, a housing defining a chamber, conductive liquid mercury disposed in said chamber and connected electrically to said second terminal means, movable circuit closing means supported by said conductive liquid so as to be upwardly biased by said liquid into contact engagement normally with said first terminal means to close said circuit of said switching device, said movable circuit closing means being inherently electrically conductve, whereby, upon movement of a circuit opening element between said circuit closing means and said first terminal means, said switching device circuit is opened, displaced fluid controlling receiving means for receiving displaced mercury, and wherein said first terminal means comprises a contact plate formed of non-magnetic material, and wherein said movable circuit closing means comprises a magnetizable body floatable on said mercury and constructed and arranged for upward bias by said liquid into circuit closing contact with said contact plate, and magnetic means constructed and arranged for exerting additional upward bias on said movable circuit closing means to enhance said circuit closing contact engagement.

3. The construction according to claim 2, wherein said magnetic means comprises a permanent magnet.

4. The construction according to claim 2, wherein said magnetic means comprises an electromagnet.

5. The construction according to claim 2, wherein said contact plate is normally disposed out of reach of said movable circuit closing means, means for moving said contact plate into position where it is engageable by said movable circuit closing means upon upward bias of said circuit closing means, and wherein said magnetic means is actuatable to move said circuit closing means into contact closing engagement with said contact plate even when there is insuflicient liquid level to effectuate such closure alone.

6. A switching device comprising a container, a conductive fluid in said container, a first electrical terminal connected to said conductive fluid, a switch closing member floating on said conductive fluid in said container and maintaining electrical contact therewith, a second electrical terminal, an upper portion of said switch closing member projecting out of said container and constructed and arranged for releasable switch closing engagement with said second electrical terminal, and for being biased into such switch closing engagement by the floating action of said conductive fluid, said switch closing member fitting smoothly within said container, and having fluid receiving overflow recesses formed in said switch closing member for receiving fluid upon excess depression of said switch closing member in said fluid.

7. The construction according to claim 6, characterized further in that there is a cam surface formed on the upper end of said switch closing member to facilitate entry therebetween of a switch opening means in the form of a tape or the like, for opening the circuit.

8. A switching device comprising a container, a couduc said conductive fluid, a second terminal disposed above said container, a switch closing spherical member fioatable on said conductive fluid for making contact therewith and normally projecting upwardly out of said container for making normally closed switching contact with said second terminal, whereby it is constructed and arranged for being depressed out of contact with said second terminal on insertion therebetween of a tape or the like with insulating qualities, and projecting means carried by said switch closing member for maintaining said member against rotation about a horizontal axis.

9. The construction according to claim 8, characterized further in that said conductive fluid is mercury.

References Cited in the file of this patent UNITED STATES PATENTS Heiltel Aug. 31, 1875 Thomas Apr. 28, 1885 Brown Apr. 14, 1896 Brown June 27, 1899 Rufie Aug. 19, 1952 FOREIGN PATENTS Great Britain Oct. 23, 1930 

